Weather is what you experience right now. It's short-term, changes hourly, and is unpredictable beyond two weeks. Climate is the long-term average of weather patterns. It's stable, changes slowly over decades, and can be predicted based on historical data.
When you check weather.refdat.com for tomorrow's temperature in Sydney, that's a weather forecast. When you look at the "average maximum temperature" for Sydney in January, that's climate data.
Climate averages are based on 30-year normals. For example, the "average maximum temperature in January" for Sydney is calculated by taking the maximum temperature recorded on each January day over 30 years, then computing the average.
Why 30 years? The WMO (World Meteorological Organization) established 30 years as the minimum period needed to smooth out natural variability and identify true climate patterns. One hot summer doesn't change the climate. Three decades of increasingly hot summers does.
Australia's climate data comes primarily from the Bureau of Meteorology's network of weather stations. ACORN-SAT is a quality-assured network of 112 long-term stations that provide Australia's most reliable historical temperature records.
These stations measure daily minimum and maximum temperature, rainfall, solar radiation, humidity, wind speed, and other variables. Data is collected at the same time each day, allowing for consistent comparisons across decades.
Australia is large, and weather stations aren't evenly distributed. Remote areas may have limited station coverage. SILO (a Queensland Government database) uses spatial interpolation to estimate climate data for areas without nearby stations.
Spatial interpolation works by measuring the gradient of variables across the landscape. If you know temperature in Brisbane and Toowoomba, you can estimate the temperature at points in between based on elevation, latitude, and prevailing patterns. This allows climate data for unmonitored locations.
Most climate charts show the same basic information:
RefDat weather pages combine this data with derived information like comfort scores, which account for temperature, humidity, wind, and UV together.
RefDat calculates comfort scores from 0-100, combining temperature, humidity, wind, and UV. A score above 80 indicates excellent comfort (warm but not hot, low wind, safe UV). A score below 40 indicates challenging conditions (very hot or cold, high wind, or dangerous UV).
Australia spans multiple climate zones. The northern tropical zone has high rainfall and humidity. Central Australia is arid with low rainfall. Southern Australia is temperate with variable rainfall. Understanding these zones helps interpret local climate data.
Climate is often classified using the Koppen-Geiger system, which categorises climates by temperature and rainfall patterns. Australia includes tropical savanna, arid desert, Mediterranean, and temperate climates.
Climate changes slowly over decades and centuries. Long-term trends can be detected by comparing 30-year normals across different periods. If the 1961-1990 normal for Perth was 30C, and the 1991-2020 normal is 30.5C, that indicates warming.
The IPCC (Intergovernmental Panel on Climate Change) uses 30-year comparisons to track global climate change. In Australia, most regions have warmed over recent decades, particularly inland areas.
Climate data helps with planning: choosing places to live, planning agriculture, designing buildings, and preparing for extreme weather. Understanding climate averages helps you prepare for typical conditions while acknowledging that extremes can occur.
Visit RefDat weather data for climate information for 213 Australian cities.
Climate data represents averages. Individual years will vary. The warmest January on record was warmer than the average. The driest year on record was drier than the average. Climate data shows what's typical, not what always occurs.